How to filter the folders that have "pdf" and "azw3" files?

I have a dir with books, my Kindle. Some folders on that dir have the same book in various file formats (Book named "Foobar", files "Foobar.azw3" & "Foobar.pdf".

I want to know which folders have a book in more than one file type. I read the dopus help file but I didn't found a way to make a filter to do that. Is there any way to do that with dopus?

Thank you.

If you go to the parent folder, then turn on Flat View so you can see all the files below it, and run a button with this command...

Select *.azw3 DeselectNoMatch Select SimilarBase Select *.azw3 Deselect Select SimilarBase will select all the files that have both *.azw3 and some other extension. (Not necessarily .PDF, as it does not confirm that. If you need that then it can be done but might be a bit more complicated.

I used your code and a filter. The filter was needed to hide everything that wasn't ".pdf" and ".azw3" but still had the same base name. That will do for now. Thank you.